Ian Jackson wrote:
In message , dave
writes



I am fully cognizant of the possibility of meaningful reactance being
introduced by a coil of Nichrome, and was hoping that someone who
deals with passive components more regularly than I could point me in
the right direction, and that has happened.

From your other post, I see that you are going to use metal oxide
resistors. In the circumstances, that's obviously the correct decision.

But your question did not ask about what were the best resistors to use
for the attenuator. It was "Can I use wirewound resistors to build an HF
attenuator?" I assumed that you knew that WW would be inductive, but
might have some reason for wanting to use them.

Ralph Mowery replied that the "Simple answer is no" etc. You responded
with "Can the inductive reactance be cancelled with capacitors? I'm
mainly concerned with 40, 30 and 20 meters" which again made me think
that you wanted to use the WW, if possible. I suggested that the effects
of the inductance might be reduced if you mounted the resistors hard
down against a ground plane. [This is a frequently-used technique for
preserving the characteristic impedance, especially at higher frequencies.]

JB then suggested "a bunch of chip resistors". I commented that you
would need quite a lot of them. It was only then that I actually
suggested that there might be a reason why you were asking about WW, and
that the application was 'only' for amateur radio. Your response was
"**** you". "How very strange", I thought!

Anyway, I'm glad you have got yourself sorted out. I hope - no, I know -
that the attenuator will definitely work as expected, with the advantage
that it will probably work way up into the VHF region.

That's way revisionist, but I am used to it. I apologize for the
vulgarity.

On Aug 18, 8:32*am, dave wrote:
I need to lose about 5 dB from a 15 Watt exciter. *Thanks.

You could build the attenuator so it takes the power down in steps
perhaps 2 1db attenuators followed by a 3db attenuator. I didnt run
then numbers but I think this is doable with 2 watt resistors.

Jimmie